Spark-plug



1, BLOIVI'STER4 AND J. SCHABEN.

SPARK PLUG.

APPLICATION FILED AUG-.8, I 9Ia.

1 ,$07,894. Patented June 24, 1919.

UNITED STATES PATENT OEEIOE.

JOEL BLOMSTER AND JOSEPH SCHAIBEN, OF ALGONA,

SPARK-PLUG.

Specification of Letters Patent. Patented June 24, 1919.

Application led August 8, 1918. Serial No. 248,887.

This invention relates to new and useful improvements in spark plugs, and the primary object of the invention is to provide a spark plug with tubular electrodes, each of which 'is provided with a check valve adapted to open on the suction stroke of the piston and close on the compression stroke whereby air may be admitted through the plug to cool and prevent the collection of oil or car-bon upon the points of the electrodes and which will at the same time cool and prevent the insulating sleeve from cracking under excessive heat.

A further object of the invention is to construct each check valve in such a manner that it can be quickly adjusted to regulate the amount of air to be admitted to each tubular electrode.

With these and other objects in view as will appear as the description proceeds, the invention comprises the various novell features of construction, combination and arrangement of parts as will befully described hereinafter and afterward specifically claimed.

Referring to the drawings,

Figure 1 represents a side elevation of our improved construction' of spark plug.

Fig. 2 represents a vertical sectional View through the same, and

Fig. 3 represents a slightly modified form of the invention.

plug provided interiorly with an annularv shoulder Q on which rests the insulating sleeve or body This insulating sleeve is provided at its bottom with a reduced sleeve fi projecting below the shoulder 2. 5 is the usual formv of collar nut threadedly connected to the upper part of the shell and serves to hold the insulating member in position within the shell. l

6 is the tubular electrode exteriorly threaded for the ygreater ortion of its length and adjustably disposedp through a central opening 7 in the lnsulating sleeve and is provided with a nut 8 adapted to bear against the bottom portion 9 of the insulat ing body, while the upper portion is provided with a washer 10 and a lool; nut l1 which coperate to hold the electrode in rigid adjusted position. 1f desirable, a Suit able packing 12 may be positioned around the electrode between the nut 8 and the bottom portion 9 of the insulating member 3.

The upper or outer end of the tubular electrode 6 has a check valve detaehably connected to it which comprises a base member 13 provided in its upper end vwith an enlarged recess 14 and in its bottom with a .threaded aperture 15 to receive the upper end of the electrode, whereby vcommunication is established between the electrodeand the recess 14.

A closure member 16 is threadedly connected onto the base member and is provided with an inwardly projecting sleeve 17 through which is slidably mounted a tubular valve member 18 provided at its lower' or inner end with a 'button head 19 and at its outer end with a fiange or cross member 20. An expansible spring 21 is positioned around the valve member between the flange 20 and theclosure member 16 and serves to normally hold the valve head 19 firmly seated against the inner end of the sleeve 17. This tubular valve member is provided adjacent the head 19 with a circumferential row of apertures 22 which when the tubular valve member is drawn inwardly on thesuction stroke of the piston of an engine establishes communication between the atmosphere and the recess 14 and the tubular electrode 6.

By the above described construction, it will be noted that by adjusting the closure member 16 upon the base member, the space 'between the end of the sleeve 17 and the bottom of the recess 14 can be either decreased or increased so as to limit and control the inward or opening movement of the llO electrode and close the entrance opening thereto.

23 indicates the other electrode 'of the spark plug and which, like the central electrode, is tu'bular and externally threaded so that it can be threaded through and adjustably mounted in the shell l and may, if desired, be provided with a lock nut 24 to hold it in adjusted posit-ion; however, it is believed that this will not vbe'necessary in the event that the electrode is tightly threaded into the shell. It is to be further noted that the electrode 23 is disposed at an angle to the central electrode 6 so that the air admittedthrough each electrode Will be directed against the points thereof to keep them clean and free from foreign matten. VIt will be noted that the two tubular electrodes converge to their lower ends, which are cut obliquely, and these oblique ends'l, confont one another with the edges substantially parallel to provide the spark gap through which the air passes. Thus, in addition to the cooling effect accomplished, an.v effective spark gap is provided, since the electrodes have continuous sparking edges opposite to and parallel with one another, extending completely around the openings:l of the electrodes. v

The upper or outer end of the tubular: electrode 23 has a check valve detachab-ly v connected to it which is identical in con-vr struction With the one just described as be- A ing connected to the central electrode 6, therefore it is believed that the description of the latter will suiice for this,

In the modified form of spark plug shown in Fig. 3, it will be noted that the central tubular electrode is provided with a cheek valve of the character hereinbefore described while the eccentric electrode 25 is simply of tubular formation and rigidly attached to the shell l in any suitable manner. While this form of plug may not be as effective in use as the preferred form, yet in some instances it may be desirable and work suiliciently Well to make it practicable.

From the foregoing description taken in connection with the accompanying drawings, We desire to have it understood that such changes in construction and arrangement of parts may be made When desired as are Within the scope of the appended claims.

What We claim is l. A spark plug having a pair of tubular air entry electrodes having their active ends confronting each other, and Check valves for said electrodes.

2. A spark plug having a pair of tubular air entry electrodes converging to their active ends said ends being cut obliquely and confronting each other, and cheek valves for said electrodes.

In testimony whereof We have signed our names to this specification in the presence of two subscribing Witnesses.

JOEL BLOMSTER. JOSEPH SCHABEN. VVitnesses:

E. J. McEvoy, PETER BORMANN. 

